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Australian Hydronic Supplies
10 Frankston Gardens Drive
Carrum Downs, Victoria,
Australia 3201
8.5 Pouring the slab
1.
Ensure that the screed used in the concrete
is suitable for underfloor heating.
2.
To avoid possible damage to the pipe the
slab should be poured at the earliest
possible opportunity after the leak test has
been completed.
3.
Ensure that the concrete vibrator probes do
not come into contact with the pipe.
4.
Care must be taken to ensure that shovels
or other hand tools do not damage pipe
work.
5.
Provide board walkways to facilitate safe
passage for wheel barrows.
6.
Minimum concrete cover above the top of
the pipe is 30mm. Maximum concrete cover
is 50mm.
7.
If the pipe is damaged during the pour,
immediately remove the wet concrete
around the damaged area and repair the
damage.
8.
Remove the damaged pipe and using
connectors replace with a new section of
pipe, then re-pressurise that circuit. Wrap
the brass connector with plastic tape to
reduce
corrosion.
8.6 Curing of the slab
9.
Once complete, the slab should be allowed to
cure naturally until full strength is obtained; this
is generally achieved at 28 days.
10.
Do not use the heating system as a
means of achieving premature curing
as damage to the slab may result.
11.
To avoid damaging pipes, trades should be
instructed not to light any fires or apply any
heat to the concrete floor.
12.
To minimize the possibility of accidental
puncturing of pipes during the construction of
the building, the pipes should be marked on the
concrete in areas where this could happen.
13.
If it is not possible to keep the system under
pressure during the concrete pour, then the
system should be pressure tested again
immediately after the pour has been
completed
.
8.7 Commissioning of the system
1
4.
Check that the system still has the original
pressure as when the slab was poured.
15.
Before releasing the pressure on the manifolds,
close all manifold circuit flow and return valves
to maintain pressure in the circuits assuring no
air can be entrapped and isolating the circuit
should a pipe be punctured during construction.
16.
Install the boiler and connect all relevant pipes,
pressure at 1 – 1.5 Bar cold.
17.
Ensure that all air is bled from the system.
18.
The boiler should be commissioned to the
manufacturer’s recommendations but at a low
flow water temperature say 30
o
C.
19.
The system should be uniformly heated with all
circuit valves fully open.
20.
Starting at 20 - 25
o
water temperature for 3
days, then slowly increasing the water flow
temperature over a period, at about 5
o
C per day
to the desired flow temperature of 45 is reached.
21.
As moisture may escape during this initial heat
up period, adequate ventilation of the building is
strongly recommended.
22.
After approximately 7 days the preliminary
balancing of the system should be performed.
23.
All floor coverings and furnishings should be
completed before final balancing is carried out.
